1. Technical Field
The present invention relates to a technology for sensing displacement and positioning an object in a real-time manner. More particularly, the present invention relates to a displacement sensing system using two image-capturing devices and a 4-matrix lookup table method to determine a coordinate-based position of an object in a specified planar area.
2. Description of Related Art
The technology of sensing displacement and positioning an object in a specified planar area defined by coordinates has been maturely applied to touch panels.
While a conventional touch panel is advantageous for its high accuracy and fast reaction, it has such disadvantage that the bigger in size the panel is made, the higher the manufacturing cost is and the higher the defective rate is.
With the attempt to reduce the manufacturing cost, some technologies using image-capturing devices, illuminated marks affixed to moving objects, and operational programs have been proposed for the purposes of calculating displacement and positions of the objects with respect to large planner areas defined by coordinates so as to obtain spatial information of the objects. For example, U.S. Pat. No. 4,672,562 titled “Method and apparatus for determining location and orientation of objects”, wherein an orthogonally related target point array is provided in fixed relationship to an object and a photo detector image plane obtains images of the target points projected through a lens located a fixed distance from the image plane so that through algebraic manipulation, spatial information about the object can be obtained.